Threading apparatus



Jam 11, 1944. B. A. RAETscH THREDILNG APPARATUS Filed Oct. 19, 1940 2 Sheets-Sheet l Jan. 11, 1944. B, A. RAETSCH 2,338,821

THREADING APPARATUS Filed Oct. 19, 1940 2 Sheets-Sheet 2 Patented Jan. 11, 19.44

UNITE-o STATES PATENT orner.

'rnnEAnmG APPARATUS Bruno A. Raetscli,

Baltimore,` Md... assigner to Western Electric Company, Incorporated,. New York, `N. Y., acorporation of New York Application yOctober 19, 1940, Serial No. 361,848

11 claims.

This invention relates to threading apparatusv and more particularly to apparatus for feeding and holding parts during the forming of internal and external threads thereon. n

It is an object of the' present invention to pro? vide a simple mechanism forfeedin'g and handling parts during the formation n, of threads thereon.

In accordance with one embodiment ofthe invention, as applied'to a part having co-axial internal and external threads', a mechanism has been provided for rechasing the threads on the parts after the parts have been galvanized. This mechanism includes an internal threading station and an external threading station in each of which there is provided means for feeding parts through a threading position and automatically ejecting ,them on the side away from the side from which they -are fed. -The apparatus at the two stations are similar insofar as the feeding mechanism is concernedv and the parts' arey fed from a magazineat each station wherein reciprocatable chuck mechanisms are provided which advance the parts to threading tools and eject a previously threaded part from the appao internal threads on the means for holding the article during the thread--` ing thereof and Fig. 7 is a.l view in perspective of the article` being threaded.

In the drawings, wherein like reference char-v i acters designate the same parts throughout the several views, Fig. 1 shows, in iront elevation, a preferred embodiment of the present invention,

.which is designed to reohase the internal and externalr threads on an article Hi, most clearly n shown in Fig. '1.v The'particular article I0, which this embodiment of handle. yhas a hexagonal head li and a partially hallowed shank I2. -The shank i2 of the article l0 has internal and external threadsformed on it in any suitable Vthreading apparatusand is then galvanized.

threads are quite frequently .clogged with the galvanizing material and it, therefore, becomes necessaryto rechase and retap the external and shank of the article;

' The present invention is directed to an apparatus ratus each time the chucking mechanism. ad,- f.

Fig. 3 is an enlarged fragmentary iront eleva.-r4`- tional view of the external *threading station shown in Figs. l` and-2;

Fig. 4 is an enlarged partly in section, of the apparatus at threading station;

Fig. 5 is a sectional view taken along the line 5--5 oi Fig. 4 in the direction of the arrows showing further details o the apparatus in the internal 'threading station;

the internal e line ii-i Fig. e in the direction .showing a portion of the chuclsing i is a front elevational view of an appak for chasing the externall side elevationalA view, l'

with the ace is ctional view, on an enlarged scale,

part is galvanized. v v .y In this embodiment of the invention, any suitable threading vdies may he used; for example, l the threading die shown in the patent to R. M.

for performing these operationsas lexpeditiouslyl as possible, although it is obvious that the present apparatus might also be used for originally forming the internal and external threads before the Strickland, No. 1,639,712', dated August 23, 1927, may be used to chase the external threads, and

` the threading die shown in the patent to H. Goldberg. No. 2,067,267, dated January l2, 1937, may be used to retap the internal threads. In the drawings, the external thread cutting mechanism has been designated generally by the numeral I5" and the internal thread cutting mechanism has been designated generally by the numeral I6.v These mechanisms may be suitably mounted with respect to a'table I1 on which the feeding mechanism is supported. Suitablymounted beneathk the table' I1 (Fig. 1)v is shown) ,which drives a belt I8 for controllingthe actuation of the two feeding mechanisms. The belt I8 drivesA a pulley i9, which is xed to a shaft 2U. The shaft 20 (Fig. 2) carries a pair of valve actuating cams 2l, 'only one of which-is shown, since the cams 2| for controlling the operation of the feeding mechanism at both of the threading stations are identical. The construction and method of operation of these cams may be seen by reference 'to Fig. 2, wherein a v'reversible valve 253 is shown, which is provided with a control arm 24 and a latch arm 25. In the the invention is designed to In the galvanizing process, the

a driving motor (not position shown in Fig. 2, the valve is inv position to direct a iluid under pressure through a pipe 26 to a, cylinder 21. The latch arm 25 is normally urged to rotate in a clockwise direction by a spring 28 to open the valve 23 and permit the fluid under pressure to be forced from the cylinder 21 back through the pipe 26.

Extending upwardly from the table |1 are suitable brackets 3|, which support the lower end of the feeding mechanisms, which are, in turn, supported on a relatively thick plate 32 fixed to the brackets 3| Mounted on the upper end of the plate 32 is the cylinder 21, in which there is vertically reciprocatable a piston 33 havingxed to it a p iston rod 34. Piyoted intermediate the ends of the plate 32 (Fig. 2) is a latch 35 for cooperation with the latch arm 25. The construction of the latch arm 25and latch 35 is such thatl when the valve actuating cam 2| strikes `the control arm 2'4, vthe latch arm25, which is 'xed to' the controlparm, will be vmoved to the position until the latch 35 is rocked in a counter-clockwise direction about its pivot.

Fixed to the piston rod 34 is a rectangular plate 36 having a set screw 31 mounted init for engaging the latch 35 and rocking it in a counterclockwise direction after the piston 33 has moved downwardly a predetermined distance. Interposed between the plateI 36 and a housing 38 and surrounding the piston rod 34 is a coil spring 38, which normally urges the piston upwardly, the housing 38 being flxed to the plate 32 adjacent the lowerend of the plate 32. The mechanis'm describedv thus far is common to the feeding apparatus at both the internal and external threading stations and has, therefore, been shown in detail only in connection with the external threading station.

Referring to Figs. 4 and 5, wherein the specic details of construction of the feeding and holding mechanism at the internal threading station are shown, the plate 36 is fixed to the piston rod 34 by means of a pin 40 and has attached to it, Yby means of a pair of set screws 4| and 42, two guide rods 43 and'44, on the lower ends of which are, in turn, mounted a pair' of guide blocks 45 and 46. The guide blocks 45 and 46 are interconnected by a yoke 41, which has an aperture 48 formed in it to receive Va reduced portion 49 of the piston rod 34, and are supported on the guide rods 43 and 44 by means of pins 53 and 50. The pins 53 and 5|) are ilxed to the blocks 45 and 46 and extend into slots and 52, respectively, in the rods 43 and 44. The lower ends of the rods 43 and 44 are hollowed out to receive springs 60 and 6|, which are held in place by threaded blocks 62 and 63, and normally tend to force the pins 53 and 50 upwardly with respect to the rods 43 and 44 to hold the pins 53 and 50 against the upper ends o1' the slots 5| and 52. In the position shown in Figs. 4 and 5, the piston rod 34 has moved downward slightly due to the admission of iluid under pressure through the pipe 26 .to the cylinder 21. However, ,theA blocks 45 and 46 have-.not .as vyet started to move downwardly with the .rods 43 and 44, since the springs 60 vand 6| are stilly holding theblocks 45 and 4 6 and their associated yoke 41 up against the upper Vinternal surfaceof the housingf38. The lower ends of the blocks 45 and 46 have stripper plates 61 and 68 fixed to them and these stripper plates are in the position shown in direct alignment with the end of a chute 68 so that articles l0 fed down the chute Y shown in Fig. 2, where the latch will hold it will move into position on the stripper plates 61 and 68.

Mounted in the lower end of the piston rod 34 is a spring pressed plunger 10,'which has a limited movement in the end of the'rod 34 V'due to the fact that the plunger has a slot 1| formed in it for receiving a pin 12, which permits movement of the plunger 10 with respect to the rod 34 under the pressure of a spring 13 seated in the hallowed-out portion of the lower end of the rod 34 and abutting the plunger 10. The extreme lower end of the rod 34 has a socket 15 formed therein, as most clearly shown in Fig. 6, for gripping four of the six sides of the head of the article I0. l

The blocks `45 and-46 are cut out to receive latches 19 and 80, which are 4pivoted on the blocks 45 and 46 at 8| and 82. These latches are designed to engage notches 83 and 84, respectively, formed in the guide rods 43 and 44 after the guide rods havemoved downwardly with respect to the guide blocks 45 and 46. `Thelatchesk16 and 80 will be cammed into locking'engagement with the notches 83 and-84 by adjustable camming pins 85 and 86, which cooperate with cam surfaces 61 and 88 formed on the latches. This camming action will `take place when the rods 43 and 44 have moved downwardly with respect to the blocks45 and46 to the point where the latches are in registry with the notches 83 and 84, whereupon continued downward movement of the rods 43 and 44 will carry the blocks 45 and 46 with them to move the cam surfaces 81 and 88 into engagement with the camming pins 65 and 86. 44 will thus be locked together until the rods move upwardlypn the return stroke of the piston 33 to bring camming surfaces 81 and 88 into engagement with camming pins 89 and 90, which are mounted on brackets 9| and 92 fixed to the housing 38. The lower end of the housing 3l (Fig. 4) has an extension |00 formed thereon, which constitutes an extension of the chute 66 and, as shown, is in direct alignment with the stripper plates 61 and 68 to hold an article I0, which has been threaded, in position A and thereby position a second article I0 in position B. The article iny position B is directly under the socket 15 formed in the end of the piston rod 34. Cooperating with the extension |00'to hold the article I0 in place thereon is a pivoted member |0|, which is pivoted on a pin |02 fixed to the yhousing 38. The pivoted member urged into engagement with the extension |00 by a spring |03 also xed to the housing 38 and will hold the articles I0, which are fed by gravity down the chute 68, in the position shown in Fig. 4

until the piston 33 is moved downwardly to carry n a tapered member |04 fixed to the blocks 45 and 46 downwardly. The tapered member 04 will engage the article |0 shown in position A as the tapered member |04 moves downwardly and will cam it to the left (Fig. 4). A camming surfacer|05 on the tapered member |04 will cam the pivoted member |0| to the left to disengage it from the article |0 shown in position "A,"

whereas the surface |06 of the tapered member,

The blocks 45 and 46 and rods 43 and` nection with the station'for forming the internal thread in the article l0, the construction of the feeding mechanism in the portion ofthe apparatus which'forms the external'f'thread is exactly the same, the only' difference being that the plate 36 provided at the external'threading station'is made somewhat longer than the plate at the internal threading station, as clearly shown in F18..

1l and mechanism is provided for opening the threading die for forming'the externalfthreads at the external threading station. This mechanism comprises a pair of rods and pivbe locked between the stripper plates arend sa and the socket 1'5'formed in the end of the piston l I'Od 34.' e y The description of the operation thus far is exactly the same for both of the threading stations. Howeven they operation is slightly differl ent for the two stations from this point onward and, therefore, the internal threading station will i" rst be described.

As the article I0 is carried downwardly by' thel a pistonrod 34, it will moveinto engagement with fthe internal threading` die |6 `and since the di'e otally mounted by means of pins ||2 and |13 f on the plate 36 and extending downwardly beside lthe housing 38. As most clearly shown in Fig. 3,

the rods |||l and yare normally urged toward the housing 38 by springs ||4 and ||5; Ther |23 of a yoke |24.` The yoke |24'is mounted inA an annular'depression |25 of the external threading die |5 and upon movement'upwardly closes the die to its operating position. Downward movement of the yoke |24 and consequent movement of a sleeve |26 of the external threading die, in which the rannular groove |y is formed, will cause the thread chasers in the die to move out of engagement with -a part which has beenA threaded, all as described in the Strickland patent mentioned! hereinbefore. This downward movement of the yoke |24 is caused by the engagementof collars |21 and |28 mounted on the rods ||0 and I vengaging the upper surface of the yoke |24 after the piston rod 34 has moved the part down sufllciently to put the desired number of threads on it.

In the operation of the apparatus, articles are fed from a` suitable hopper (not shown) into the chutes 69 at yeach of the threading stations and ride down the chutes by gravity until one of the articles I0 abuts the pivoted membel 'IUI e in each threading station, whereupon the motor (not shown) may be started to drive theshaft 20. At the first revolution of the shaft 20, the valve actuating cam 2| in each threading station will strike the control arm 24 to move it to the position shown in Fig. 2, where it will be latched in place by the latch 25 in each threading station. The control arm 24 in the position shown will permit iluid under pressure to flow into the pipe 26 and cause the pistons 33 to move downwardly. yAs the pistons 33 start tomove downwardly, carrying with them the piston rod 34,

the spring 39 will be compressed and the rods- 43 and 44 will move downwardlyv with respect to the blocks 45 and 46, the springs Wand 6| expanding to hold the blocks 45 and 46 in the.

position'shown in Figs. 4 and 5 untilthe ends of the rodsl 43 and 44 engage the stripper plates v 61 and 68 and the enlarged portion of the piston 34 engages the upper surface of the. yoke 41. In moving downwardly to the position where the enlarged portion of the piston 34 engages the yoke 41, the plunger 1|) will first engage the head of the article .Illiandthen will be held bythe article l0, compressing spring .1.3 while/the socket 'v formed in the en d of lthe piston rod 34 'surrounds the head of the article I0; Continued ldownward k'movement of the piston 1jodp34willcarry the blocks 45 and 46 with it "and the article f-|0f will I6 is constantly rotating',- the internal thread will' be formed inthe article ||J during the downward latch 35, the latch 35 will release thelatch arm 25 and permit the spring 28 to rock the latch rarm 25and control yarm 24 in a clockwise direction to permit the iluid under pressure tobe exhausted fro-rn'the cylinder 21 by the action oi? the spring 39 in pushing the piston rod 34 uD- Y wardly. As soon as the piston rod 34 starts to l return to its kupward position, the 'direction of rotation of the internalthreading die' A|6 will be.

reversed, as described inthe patent to `'Goldberg noted hereinbefore, andthe article l0 will be moved back to position in alignment with vthe end of the chute 69. a

As the piston rod 34l moveddownwardly, and in its downward movement picked up the blocks 45 and' 46 to' carry them downwardly, thetapere'd'member |04 also moved downwardly and, in its downward travel, performed two functions. One of these functions was the camming of lthe pivoted member |0| tothe left (Fig. k15)` out of engagement with the article l0 `in position A. 'I'he other function of the tapered member |04 was the camming. of the article I0 in position .fi" out of that position'to the left. As the pis ton 34 reaches its uppermost position and the socket in the end of the piston rod is drawn" oli the head of the Iarticle l0, the plunger 10 will force the article l0 outl of Athe socket in the piston rod and as soon as the tapered member |114 clears the end of the article I0, which has" had an internal thread Vformed in it, vthe weight of the other articles I0 in the chute 69 will move the article I0 at-that time in position B over to position A" and the next time that thepiston rod 34 moves downwardly, the part which .e

has just been threaded will be removed from the apparatus, as just described.

During the downward movement o-f the piston rod 34, the notches 83 and 84 formed in the rods 43 and 44 moved intol registration with` the latches` 19 and 18, respectively, and as the blocks 45 and 46 started t0 move downwardly with the piston rod 34, the camming pins 85 and 86 cammed the latches 19 and 80 into the notches 83 and 84,

whereby the blocks 45 and 46, with the stripperl` .plates 61 and 68 on the bottom of them, served to lock the article I0 in the socket in the end of the piston rod 34 and hold this assembly ltogether until the piston rod, in its upward movey ment, carried the c'amming surface's 81 and 88 of the latches 19'and k8|! into operative engagement with the pins 89 and 90 to unlatch the rods 43 and 44 from the blocks 45 and 46.

The operation of the apparatus in the `external threading 'station is exactly the same insofar as the feeding 'of parts is concerned, but the control for the external threading die operates in addition" to' those operations described hereinbefore,

Athe yoke |21. The rods |||l and do not perform any function until the collars |21 and |28 engage the upper surface of the yoke |20, at which time the threading on the outside of the article III will'be completed and continued downward movement of -the piston. rod 3lv will cause the sleeve |26 to move downwardly -to open the threading die |5-,just prior to the time when the piston rod 34 startsv to move up again. After the piston rod 3l moves upwardly a sufficient distance to clear the article I0 from the thread- `ing die I5, the extensions and |2| will engage the surfaces |22 and |23 to move the sleeve |26 -upwardly and close the threading die l5 inpreparation for threading a, succeeding article 0.

Although a specific embodiment of the invention has been described hereinbefore, it will be understood that some modifications thereof may be made without departing from the invention, which. is to be limited only by theappended claims.

What isclaimed is:

1. In a threading apparatus, a rotatable threading die, an article holding means comprising a stripper plate and a piston rod having a socket in it, guiding means initially. movable with respect to said piston and then movable with said piston rod to carry an article into association with the threading die, and means fixed to .the guiding means for ejectlng a previously Vthreaded part. Y y

v 2. In a threading apparatus, a rotatable threading die, 'an varticle holding means comprising a stripper plate and a piston rod having a socket in it, guiding means initially movable Iwith respect to said piston and then movable with said piston rod to carry an article into association withthe threading die, and means fixed tothe guiding means for ejectlng a previously threaded part, said ejectlng means including an abutment cooperating with the plunger for restraining movement of an .article being threaded.

3. In a threading apparatus, a rotatable threading die, a chute for conducting parts toward a position in alignment with said threading die, a movable stripper means forming a continuation of said chute in one of its positions, means for supporting said stripper means, a member initially movable with respect to said supporting means and strlppermeans', means for locking said member and supporting and stripping means together upon movement of the member in one direction, and means for unlocking said locked together parts on movement of the member in the 'opposite direction.

4. In a threading apparatus, a reciprocatable piston, means for normally urging the piston into a predetermined position, means for driving the piston in the opposite direction, means connected to said piston for engaging an article to be threaded to hold said article against rotation,` clamping means associated with said last mentioned means for holding an article during bodily movement thereof, and means for latching said clamping means "to the holding means comprising apair of latches, a ci acti'iator for the clamping means, and camming means'for camming the latches into latching 'engagement with the rods.

5. In a threading apparatus, a chute fory feeding articles to position to be threaded, a support 'for articles in said position, a threading die in vertical alignment with articles held in said position, means for holding the articles and mov-l ing them vertically into operative engagement with the threading means, a stop member for normally restraining movement of articles through said chute, and means on the article holding and movingmeans for rendering the stop member inoperative.

6. In a threading apparatus, a chute forfeed- I' ing articles to position to be threaded, a support for articles in said position, a threading die in vertical alignment with articles held in said poy piston, a spring for normally holding said pistonY in a predetermined position, a piston rod attached to said piston, a cross plate secured to said piston rod, a pair of actuator rods attached to said cross plate, clamping means mounted on said actuator rods for cooperating with the piston rod. to hold parts during the threading thereof, ejectlng means mounted on said clamping means for ejectlng parts after they have beenthreaded. a pair of rods pivoted on said cross plate and normally urged toward each other, extensions formedon said rods for cooperation with a die controlling yoke to close said die, and sleeves mounted on said rods for cooperation with the die controlling yoke to effect opening of said die upon a predetermined amount of movement of f said cross plate.

8. In a threading apparatus, means for feedi ing articles in one plane, a rotatable threading die, means for feeding articles at an angle to the plane of feed 'of the aforementioned feeding means and into and out of operative association with said threading die, and means on said second feeding means independent of the articlesl being Worked` on for positively ejectlng a threaded article at right angles to said second feeding means.

9. In. a metal working apparatus, means for supporting an article to be worked on, means for working on said article, means for causing said article supporting member to move the article into and out of operative engagement with said article working means, and means independent of the articles being workedvon associated with said article supporting means for positively electing an article therefrom. n

l0. In a threading apparatus, a uid actuated piston, a spring for normally holding said piston controlling yoke to close said die, and sleeves mounted -on said rods for cooperation with the a reciprocable member having edges normally in alignment with the edges of said slot for receiving an article, means for moving down over the' head of an article in said member and then moving said member and said article toward said threading member and into engagement therewith, and means independent of the articles being Worked on for ejecting athreaded article from said reciprocable member.

BRUNO A. RAETSCH. 

